1. Field of the Invention
The present invention relates to an audio-visual alarm apparatus for use with a water quality monitor in providing a detectable alarm when the water quality measured by the monitor falls outside of an acceptable quality range. More particularly, the invention relates to an audio-visual alarm apparatus that is adaptable for use with any of a number of different kinds of water quality monitors and which is positionable remote from the monitor to which it is connected.
2. Discussion of the Prior Art
It is conventional to employ reverse osmosis deionization of water for use in hospitals for specialized applications such as hemodialysis. Because the treated water comes into contact with the blood of a patient as the blood is processed in the dialysis equipment, it is necessary to provide "ultra-pure water" from which all potentially dangerous contaminants have been removed.
Numerous water treatment systems are known for processing water in order to obtain ultra-pure quality acceptable for use in conventional dialysis equipment. In addition, these systems and others include water quality monitors capable of measuring either the conductivity or resistivity of the water being processed in order to provide an indication of the water quality achieved by the treatment system in
Because of the close communication between water used in hemodialysis and blood treated in the process, catastrophic consequences may result if the treatment system fails or the quality of the water delivered from the system falls outside of an acceptable quality range. Therefore, it is necessary to provide a system for warning the health professionals supervising the hemodialysis process when such conditions occur.
A known water quality monitor for use with a conventional treatment system includes a control unit at which it is possible to set an acceptable water quality range, and a pair of contacts across which electrical conditions are indicative of whether the measured water quality is inside or outside of the preset range. Thus, a means is provided on the monitor for signaling an alarm which may be connected to the contacts so that the alarm is energized when the measured quality falls outside the preset range.
In certain conventional monitors, an alarm is included on the apparatus, and provides a visual indication of the quality of water being delivered from the treatment system. Unfortunately, because water treatment systems are often stored in separate utility rooms of a hospital, they are frequently out of range of health professionals to whom the alarm would have significance. In addition, where only visual indicators are used, there is a possibility that the health professional will misinterpret the meaning of the indicator and assume that the water quality is within the acceptable range when the indicator is lit.
An alternate proposed solution to the need for an effective alarm is to connect the monitor to a centralized processing unit located at a remote location in the hospital, and to connect the processing unit to an alarm that is located in the vicinity of the dialysis equipment. However, this system is expensive and complex, and relies upon the dependability of the entire system in delivering the required alarm signal to the person standing over the dialysis equipment.